This invention relates in general to magnetic tape recording/reproducing apparatus and, more particularly, this invention relates to a new and improved brake assembly for the supply and take-up reels of magnetic tape recording/reproducing apparatus.
Helical scan magnetic tape recording/reproducing apparatus are widely used to record analog or digital information on slant tracks on magnetic tape. Generally, the magnetic tape is transported between supply and take-up reels past a rotary head scanner. The supply and take-up reels may be mounted on the apparatus either in a coplanar relationship or in a coaxial relationship. As the magnetic tape is transported, it is necessary to maintain a uniform tension on the tape in order to effect accurate recording and reproducing of information relative to the tape. Moreover, since the tape may be transported between the reels at different speeds and in forward and reverse directions, the tension applied to the tape must be changed to accommodate such changes in speed and direction. Typically, tension is maintained by applying a braking torque to the supply reel. A reel brake is also utilized to bring the reel to a stop when the recording/reproducing apparatus is operated in a mode requiring the tape to be stopped.
It is desirable that a reel braking arrangement be simple, effective and reliable for the application for which it was designed. Moreover, with the ever increasing compactness of magnetic tape recording/reproducing apparatus, it is desirable that a reel braking arrangement be as compact as possible. Known reel braking arrangements, generally, do not satisfy all of these requirements. Thus, U.S. Pat. No. 3,638,881 issued Feb. 1, 1972 Inventor Mirkovic; U.S. Pat. No. 4,079,899, issued March 21, 1978, Inventor Vogel; and U.S. Pat. No. 4,542,864, issued Sept. 24, 1985, Inventor Hart, disclose a braking arrangement for a reel including a braking shoe mounted on a lever which is pivoted at one end and connected at its other end to a spring and solenoid. Such arrangements are mechanically complex requiring several mechanical elements which are subject to breakdown. Moreover, such arrangements are space consuming and not efficiently used in magnetic tape recording/reproducing apparatus where space is at a premium.